Network, network, network. Referrals are the prime driver of business for many, if not most, freelancers. When you get a client and have done good work, ask them "what three other people do you know who could use my services?"...things like that. Don't be afraid to ask for it. Get out of the home office and attend events and conferences. Start meeting people and ASK for their business. Don't be shy about it.

Also, don't expect much from cold emails. It's way too impersonal. Telephone calls are only slightly better, but in-person events are by far the best. Your goal should be to MEET as many people in-person as possible.